title: The brain dynamics of rapid perceptual adaptation to adverse listening conditions.
abstract: Listeners show a remarkable ability to quickly adjust to degraded speech input. Here, we aimed to identify the neural mechanisms of such short-term perceptual adaptation. In a sparse-sampling, cardiac-gated functional magnetic resonance imaging (fMRI) acquisition, human listeners heard and repeated back 4-band-vocoded sentences (in which the temporal envelope of the acoustic signal is preserved, while spectral information is highly degraded). Clear-speech trials were included as baseline. An additional fMRI experiment on amplitude modulation rate discrimination quantified the convergence of neural mechanisms that subserve coping with challenging listening conditions for speech and non-speech. First, the degraded speech task revealed an "executive" network (comprising the anterior insula and anterior cingulate cortex), parts of which were also activated in the non-speech discrimination task. Second, trial-by-trial fluctuations in successful comprehension of degraded speech drove hemodynamic signal change in classic "language" areas (bilateral temporal cortices). Third, as listeners perceptually adapted to degraded speech, downregulation in a cortico-striato-thalamo-cortical circuit was observable. The present data highlight differential upregulation and downregulation in auditory-language and executive networks, respectively, with important subcortical contributions when successfully adapting to a challenging listening situation.
authors.affiliation: Max Planck Research Group Auditory Cognition, Max Planck Institute for Human Cognitive and Brain Sciences, 04103 Leipzig, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Erb
authors.forename: Molly J
authors.initials: MJ
authors.lastname: Henry
authors.forename: Frank
authors.initials: F
authors.lastname: Eisner
authors.forename: Jonas
authors.initials: J
authors.lastname: Obleser
mesh_terms: D000161:Acoustic Stimulation; D000223:Adaptation, Psychological / Q000502:physiology*; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D032882:Comprehension / Q000502:physiology; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D017072:Neostriatum / Q000502:physiology; D009415:Nerve Net / Q000502:physiology; D009622:Noise; D010100:Oxygen / Q000097:blood; D011597:Psychomotor Performance / Q000502:physiology; D013067:Speech Perception / Q000502:physiology; D013068:Speech Production Measurement; D013788:Thalamus / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen